code: def venv(known_paths):
      global PREFIXES, ENABLE_USER_SITE
  
      env = os.environ
      if sys.platform == "darwin" and "__PYVENV_LAUNCHER__" in env:
          executable = sys._base_executable = os.environ[
              "__PYVENV_LAUNCHER__"
          ]
      else:
          executable = sys.executable
      exe_dir, _ = os.path.split(os.path.abspath(executable))
      site_prefix = os.path.dirname(exe_dir)
      sys._home = None
      conf_basename = "pyvenv.cfg"
      candidate_confs = [
          conffile
          for conffile in (
              os.path.join(exe_dir, conf_basename),
              os.path.join(site_prefix, conf_basename),
          )
          if os.path.isfile(conffile)
      ]
  
      if candidate_confs:
          virtual_conf = candidate_confs[0]
          system_site = "true"
          # Issue 25185: Use UTF-8, as that's what the venv module uses when
          # writing the file.
          with open(virtual_conf, encoding="utf-8") as f:
              for line in f:
                  if "=" in line:
                      key, _, value = line.partition("=")
                      key = key.strip().lower()
                      value = value.strip()
                      if key == "include-system-site-packages":
                          system_site = value.lower()
                      elif key == "home":
                          sys._home = value
  
          sys.prefix = sys.exec_prefix = site_prefix
  
          # Doing this here ensures venv takes precedence over user-site
          addsitepackages(known_paths, [sys.prefix])
  
          # addsitepackages will process site_prefix again if its in PREFIXES,
          # but that's ok; known_paths will prevent anything being added twice
          if system_site == "true":
              PREFIXES.insert(0, sys.prefix)
          else:
              PREFIXES = [sys.prefix]
              ENABLE_USER_SITE = False
  
      return known_paths
  
imports: import sys
  import os
  import builtins
  import _sitebuiltins
  import io
label_desc: Use image node_id 20 for calling a global function with example usage: venv(known_paths) and returns: known_paths